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Full-Text Articles in Engineering

Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown Sep 2019

Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown

Sarah Cady

In this study, we methylated hydroxyl groups (phenolic hydroxyl: Phe-OH and aliphatic hydroxyl: Aliph-OH) in soda lignin (SL) prior to solvent liquefaction to improve storage stability of the resulting oil. We investigated two methylating reagents, dimethyl sulfate (DMS) and dimethyl carbonate (DMC), for selective Phe-OH and total hydroxyl group (Phe-OH and Aliph-OH) blocking. Samples of SL, DMS-SL, and DMC-SL were depolymerized into oils under supercritical ethanol (350 °C). Both methylated lignins produced higher amounts of oils and smaller amounts of char compared to untreated SL due to suppressed charring reactions. Oil produced from SL had relatively higher functional group contents ...


Promoting Microbial Utilization Of Phenolic Substrates From Bio-Oil, Kirsten Davis, Marjorie R. Rover, Davinia Salvachúa, Ryan G. Smith, Gregg T. Beckham, Zhiyou Wen, Robert C. Brown, Laura R. Jarboe Jul 2019

Promoting Microbial Utilization Of Phenolic Substrates From Bio-Oil, Kirsten Davis, Marjorie R. Rover, Davinia Salvachúa, Ryan G. Smith, Gregg T. Beckham, Zhiyou Wen, Robert C. Brown, Laura R. Jarboe

Mechanical Engineering Publications

The economic viability of the biorefinery concept is limited by the valorization of lignin. One possible method of lignin valorization is biological upgrading with aromatic-catabolic microbes. In conjunction, lignin monomers can be produced by fast pyrolysis and fractionation. However, biological upgrading of these lignin monomers is limited by low water solubility. Here, we address the problem of low water solubility with an emulsifier blend containing approximately 70 wt% Tween® 20 and 30 wt% Span® 80. Pseudomonas putida KT2440 grew to an optical density (OD600) of 1.0 ± 0.2 when supplied with 1.6 wt% emulsified phenolic monomer-rich product produced ...


Exploring Methodologies To Improve Lignin Utilization In Biorefineries, James Meyer May 2019

Exploring Methodologies To Improve Lignin Utilization In Biorefineries, James Meyer

Engineering and Applied Science Theses & Dissertations

The increasing world population, coupled with an improving quality of life, has driven a rapidly increasing demand for fuels, chemicals, and materials. Fossil carbon feedstocks, such as petroleum, are currently being consumed to meet these demands. The utilization of these feedstocks has negative impacts on human and environmental health, which are undoubtedly intensifying as a result of the increased reliance required to meet these demands. As an alternative way to meet these demands, biorefineries generate a wide range of fuels, chemicals, and materials from biomass, a renewable and sustainable resource. Current second-generation biorefineries use a plant-based feedstock, lignocellulosic biomass, comprised ...


Bio-Based Thiol-Ene Polymer Electrolytes, Elyse Antonia Baroncini Mar 2019

Bio-Based Thiol-Ene Polymer Electrolytes, Elyse Antonia Baroncini

Theses and Dissertations

Industrial and consumer demand for smaller and safer technologies motivates a global research effort to improve electrolytic polymer separators in lithium-ion batteries (LIBs). To incorporate the aromatic structural advantages of lignin, an abundant and renewable resource, into polymer electrolytes, molecules that can be derived from lignin are functionalized and UV-polymerized with multifunctional thiol monomers. Monomer aromaticity, thiol molecular weight, and total functionality are varied, allowing for analysis of the relationships between polymer structure and electrochemical properties.

The synthesized polymers display conductivities on the order of 10^-5 S/cm for gel polymer electrolytes and 10^-4 S/cm for solid ...


Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown Jan 2019

Pre-Methylation Of Lignin To Improve Storage Stability Of Oil Produced By Solvent Liquefaction, Jae-Young Kim, Parinaz Hafezi-Sefat, Sarah D. Cady, Ryan G. Smith, Robert C. Brown

Mechanical Engineering Publications

In this study, we methylated hydroxyl groups (phenolic hydroxyl: Phe-OH and aliphatic hydroxyl: Aliph-OH) in soda lignin (SL) prior to solvent liquefaction to improve storage stability of the resulting oil. We investigated two methylating reagents, dimethyl sulfate (DMS) and dimethyl carbonate (DMC), for selective Phe-OH and total hydroxyl group (Phe-OH and Aliph-OH) blocking. Samples of SL, DMS-SL, and DMC-SL were depolymerized into oils under supercritical ethanol (350 °C). Both methylated lignins produced higher amounts of oils and smaller amounts of char compared to untreated SL due to suppressed charring reactions. Oil produced from SL had relatively higher functional group contents ...


Nb(Ta)-Based Solid Acid Modified Pt/Cnts Catalysts For Hydrodeoxygenation Of Lignin-Derived Compounds, Weixiang Guan, Xiao Chen, Chuang Li, Jie Zhang, Chi-Wing Tsang, Haoquan Hu, Shaojie Li, Changhai Liang Jan 2019

Nb(Ta)-Based Solid Acid Modified Pt/Cnts Catalysts For Hydrodeoxygenation Of Lignin-Derived Compounds, Weixiang Guan, Xiao Chen, Chuang Li, Jie Zhang, Chi-Wing Tsang, Haoquan Hu, Shaojie Li, Changhai Liang

Technological and Higher Education Institute of Hong Kong (THEi) Staff Publications

Efficient upgrading of lignin bio-oils into oxygen-free liquid alkane fuels is a challenging task owing to the incompatibility of the phenolic feedstock with conventional fuels and the availability of effective hydrotreating catalysts based on the current refinery infrastructure. In this work, a series of solid acid nanosheets (HNbWO6, HNbMoO6, HTaWO6) modified Pt/CNTs bifunctional catalysts were evaluated in hydrodeoxygenation (HDO) of lignin-derived compounds. The effects of types of nanosheets and the synergistic effect between metal sites and acid sites were discussed via HDO of diphenyl ether. Pt/HNbWO6/CNTs catalyst exhibited the most efficient performance for the HDO of diphenyl ...


Comparison Of Product Distribution, Content And Fermentability Of Biomass In A Hybrid Thermochemical/Biological Processing Platform, Zhanyou Chi, Xuefei Zhao, Tannon Daugaard, Dustin Dalluge, Marjorie Rover, Patrick Johnston, Andre M. Salazar, Miguel C. Santoscoy, Ryan G. Smith, Robert C. Brown, Zhiyou Wen, Olga A. Zabotina, Laura R. Jarboe Jan 2019

Comparison Of Product Distribution, Content And Fermentability Of Biomass In A Hybrid Thermochemical/Biological Processing Platform, Zhanyou Chi, Xuefei Zhao, Tannon Daugaard, Dustin Dalluge, Marjorie Rover, Patrick Johnston, Andre M. Salazar, Miguel C. Santoscoy, Ryan G. Smith, Robert C. Brown, Zhiyou Wen, Olga A. Zabotina, Laura R. Jarboe

Chemical and Biological Engineering Publications

Thermochemical processing is a promising method for the rapid depolymerization of biomass. This study investigated switchgrass, corn stover, red oak, hybrid poplar, and loblolly pine in terms of heteropolymer and elemental composition, and the distribution and composition of the fast pyrolysis products. Corn stover differed from other biomass types in that less of the biomass was recovered as sugar or phenolic oil (PO) and more of the biomass was recovered as bio-char and bio-gas. The sugar-rich aqueous stream recovered from the bio-oil heavy fraction was characterized in terms of sugar content and distribution, inhibitor content, and ability to support production ...